It is known that an artificial lung in which blood can flow perpendicularly to a hollow fiber membrane can achieve gas exchange with high efficiency and a low pressure drop due to effective fracture of blood-side laminar film resistance, and has high efficiency in basic performance. Further, the artificial lung in which a heat exchange pipe bundle is laminated on a hollow fiber bundle performs heat exchange as well as gas exchange, thereby performing an operation for maintaining the temperature of blood in an appropriate range effectively. Such a hollow fiber membrane-type artificial lung described in Patent Document 1 or 2 will be described below with reference to FIG. 5.
The hollow fiber membrane-type artificial lung shown in FIG. 5 has a housing that includes a gas exchange part 21 and a heat exchange part 22 that are piled up. In bores of the gas exchange part 21 and a heat exchange part 22, a hollow fiber bundle that is a bundle of hollow fiber membranes 28, which are elements for the gas exchange, and a stainless pipe bundle that is a bundle of stainless pipes 29, which is an element for the heat exchange, are stored, respectively.
The hollow fiber bundle has a form in which a plurality of the porous hollow fiber membranes 28 are arranged and laminated such that an axial direction thereof is a horizontal direction. The stainless pipe bundle has a form in which a plurality of the stainless pipes 29 constituting heat exchange pipes are arranged and laminated such that an axial direction thereof is the horizontal direction. The stainless pipe 29 and the hollow fiber membrane 28 are arranged such that the directions of arranging the respective axes are parallel with each other.
In a circumferential region including both end parts of the hollow fiber membranes 28, a potting material is filled so as to form a potting part 30a. A bore of the potting part 30a forms a cylindrical blood channel that extends across the hollow fiber membranes 28 in a perpendicular direction. The potting material is filled also in a circumferential region including both end parts of the stainless pipes 29, thereby forming a potting part 30b. Also, a bore of the potting part 30b forms the cylindrical blood channel that extends across the stainless pipes 29 in the perpendicular direction.
In a boundary part between the gas exchange part 21 and the heat exchange part 22, outer shell walls of both parts are opened so as to form an opening gap part 33. The cylindrical blood channel that is formed by the potting part 30a of the hollow fiber bundle and the cylindrical blood channel that is formed by the potting part 30b of the stainless pipe bundle 29 are communicated with each other via the opening gap part 33, thereby forming the blood channel that is continuous in the perpendicular direction. On the outer shell walls of the heat exchange part 22 and the gas exchange part 21 that respectively correspond to an top end and a bottom end of the blood channel, a blood inlet port 23a and a blood outlet port 23b are provided.
At a left end part and a right end part of the gas exchange part 21, gas headers 24a, 24b for sealing the bores are provided, respectively. To the gas headers 24a, 24b, a gas inlet port 25a and a gas outlet port 25b are provided, respectively. Moreover, at a left end part and a right end part of the heat exchange part 22, cold/hot water headers 26a, 26b for sealing the bores are provided, respectively. To the cold/hot water headers 26a, 26b constituting the heat exchange headers, a cold/hot water inlet port 27a and a cold/hot water outlet port 27b for allowing cold water or hot water that is a heat exchange liquid to flow in and out are provided, respectively.
Blood that flows in from the blood inlet port 23a passes through the blood channel that is constituted of the bore of the potting part 30b, the opening gap part 33 and the bore of the potting part 30a, and flows out from the blood outlet port 23b. 
Gaps 31a, 31b are formed near both ends of the hollow fiber bundle, by the gas headers 24a, 24b that respectively are provided on the left side and the right side of the gas exchange part 21, and the hollow fiber membrane 28 forming the hollow fiber bundle are opened to the gaps 31a, 31b on end faces of the potting part 30a. Thus, an oxygen-containing gas that flows in from the gas inlet port 25a fills in the gap 31a, enters the bore from one end of each follow fiber membrane 28, passes through the gap 31b from the other end of each follow fiber membrane 28, and then flows out from the gas outlet port 25b. During this time, the gas exchange is performed with the blood.
Moreover, gaps 32a, 32b are formed near both ends of the stainless pipe bundle 29, by the cold/hot water headers 26a, 26b that respectively are provided on a left side and a right side of the heat exchange part 22, and the stainless pipe constituting the stainless pipe bundle 29 is opened to the gaps 32a, 32b on end faces of the potting part 30b. Thus, the cold water or the hot water that flows in from the cold/hot water inlet port 27a fills in the gap 32a, enters the bore from one end of each stainless pipe, passes through the gap 32b from the other end of each stainless pile, and then flows out from the cold/hot water outlet port 27b. During this time, the heat exchange is performed with the blood.
Patent document 1: JP 11 (1999)-206880 A
Patent document 2: JP 9 (1997)-509351 A